As is known, horizontal stabilizers are used to stabilize the attitude of an aircraft and to control it about its lateral axis, the latter with the aid of an aileron, which is provided on the horizontal stabilizer. Furthermore, the aileron is trimmed in order to set the desired attitude, corresponding to the pitch angle of the aircraft, for take-off, climbing flight, cruise flight, landing approach and landing, as well as, for example, for a rapid descent in an emergency. In present-day designs of commercial airliners and transport aircraft, the horizontal stabilizer is arranged at the aft end of the aircraft fuselage.
In order to set the pitch angle as explained above, the horizontal stabilizer can be trimmed such that it selectively produces positive or negative lift, or is neutral. Conventional horizontal stabilizers can for this purpose be moved about an axis running parallel to the aircraft lateral axis, so that they can be trimmed over a predetermined angle range of, for example, +3° to −15°. In this case, angles with a positive mathematical sign, such as +3°, mean trimming of the horizontal stabilizer in the aircraft longitudinal direction (X) seen from above, which is associated with an increase in the positive lift of the horizontal stabilizer, and thus with rotation of the aircraft about its lateral axis in the sense of reducing the pitch angle, while angles with a negative mathematical sign, such as −15°, mean trimming of the horizontal stabilizer downwards, so that the horizontal stabilizer produces negative lift, thus resulting in an increase in the pitch angle of the aircraft. In the case of conventional horizontal stabilizers, the magnitude and direction of the aerodynamic force is produced, that is to say positive lift or negative lift, is varied by varying the incidence angle of the horizontal stabilizer. In the case of conventional horizontal stabilizers, the trimming is typically carried out by means of a spindle drive, which acts on the rearward end of the horizontal stabilizer, which is mounted, connected by hinges such that it can rotate about the lateral axis of the aircraft, at its front end.